Clutch



E. E. wArrE CLUTCH Jan. 20, 1931.

Filed Jan. 19, 1928 I N VEN IOR. in-az,

Ahh *Ah APH: AAAAAMMMMPAMAB Patented Jan. 20, 1931 UNITED STATES PATENT oF-FICE EDWIN E. WAITE, oF-KFRAMINGHAM, MASSACHUSETTS. 'Assreivloa or CNE-HALF To MULTIBESTOS COMPANY, OF` WAL-POLE, MASSACHUSETTS, A CORPORATION F MASSACHUSETTS f CLUTCH li'lppli'uzatonf filed January 19, 1928. 'Serial No. 247,773.

This invention relates to clutches and will a facingr or lining of some friction n'iateri-al,`

such as asbestos. betweenv the driving and driven elements of a clutch. In adisk-clutcli, for example,each disk off one. set usually has T an asbestos facing riveted to 'one or both sides thereof.

The present invention is especially concerned with that type of clutch disk or equivalent element in which the facing is built 2 into the body of thedisk or element and is inseparable from it, the facing and the body n'ielnber to which it is united forming a single article of manufacture. ailns to improve the construction of clutch elements of this character and to effect econoni-ies in the niaiiizufacture of such devices.

The nature of the invention will readily understood from the following description when read in connection with the accennpanying drawings, and the iro-vel' features will be particularly pointed out in the appended claiins.`

In the drawings,` Figure 1 is a plan view of a` clutch disk constructed in accordance with this invention;

Fig. 2 is a plan view on a larger scale of a ),ortion of the .disk shown in Fig. l, but showing only a `portion of the friction facing 40 ofthe diei; f

Fig. 3 a perspective vie-w illustrating one method of forminga friction facing on the disk;` f Y Fig., 4 is a similar View showing a slightly different method; and

Fig. 5 shows a modified construction of disk body.

of a metal plate 2' having the form 4of a` Hat ammlus and provided on, its outer-edge with The invention teeth to cooperate Wit-h the ribs, splines, or

other driving elements with which a disk clutch commonly is equipped. The diskQ is provided with a Series of narrow slotsllL preferably extending radially thereof and separated freni eachother by narrow bars 5.

As shoWn, each slot is of uniform width sub- `stantially throughout' its length, While thev bars nacrease'in Width very slightly as they extend away fronrthe center ofthe disk.

Preferably, also, these slots are independent y of each other and terminate at points in the margins of the disk so that an unbroken rini ofmetal is provided at both outer edges off-the disk.

The friction facing for this clutch element consists of yarn, or equivalent material, which can be handled in the saine manner, preferably made of asbestos libre and Stitched into the slots 4. The stitches may be inad'e eithernbiy crocheting, knitting, or sewing.`

the inner and Preferably the'yarn. is stitched into the slots n by =`a sewing machine which may be'eitherof the chain stitch er lock stich type.'

As shown inFig. 3, two chain stitch sewing machines are used, 'one of these machines having a-'needle Z extending downwardly,While the; other has a needle 8 extending upwardly, and both machines Working simultaneously to stitch the filling into the slots. With this arrangement yone `mach-ine dra-Ws stitches toward one face of the disk, While the other draws its stitches toward the opposite face of the disk. In each chain stitch there is a loop a at oneI Sidel of the work so that in each row o-.r linefof chain stitches there are two` strands of yarn on one side of the disk and only onestrand on the other. Thus by drawing the stitches in 'alterna-te lines of stitching toward opposite faces ofthe disk, the saine amount of yarn isdisposed on each side of the disk. It is usually more convenient to start the Stitching operation at the inner ends of the slots 4:, stitcliing in eirciunferentially the innermost line or lines of stitching first and then stepping the disk in slightly for the stitching in of the next circumferential line or lines' of Stitching, these operations being repeated until they slots are substantially filled. Each circumferential 1in-e, of stitches,

thus lies outside or farther away from the centeil of the disk than the preceding line but they all lie side by side and thus form a. substantially continuous asbestos facing on each side of the disk. Preferably each stitch is beaten inwardly in a radial direction `inst after being formed, and the length of he stitches is increased in successive lines of stitching` to accommodate the gradual increase in the width of the bars It will be observed that this method interloeks the facing securely with the bars of the disk, since the bars extend through the loops of the individual stitches. The facing thus is built into the disk and is inseparable from it. `Since the interlocking of portions of the varn at the ends of each stitch occurs at or in the slots. the bunchin 0 of the vai-n which othl C u erwise would be produced by such interlocking is so located as to leave a smooth surface at each side of the disk. The completed disk is shown in l? ig. l, the facing being indicated at9.

I? t shows a novel stitch which I prefer to use instead of the ordinary chain stitch. T his is a modified chain stitch made with two threads or yarns and c. The thread b is manipulated to make the usual chain stitch while the thread c is simply given one turn around the thread b at the shank of each loop, the thread c remaining on the opposite side of the disk from the interlocked loops of the chain'stitches. Each line of stitching produced in this manner thus has two strands of yarn on each face of the disk. Usually it is preferable to have the needle draw the stitches downwardly instead of upwardly as Y indicated in Fig. el, this figure showing the line of stitches upside down. The thread 0 may be manipulated by a thread finger in such a manner that it will` simply give the thread one t-urn around the shank of the needle asA the needle is projected to take the Vtln'ead for each new stitch.

After the making operations have'bcen completed, the facing may be impregnated with a material which binds the asbestos 'libres together and gives the facing approximately t-he desired co-etlicient of friction. For this purpose the binders ordinarily used in impregnating woven clutch facings and brake linings may be employed. A great variety of such binders are used in this art so that no specific composition need be given. Home of these binders are of a rubbery nature while others depend chiefly upon a drying oil or asphaltic substance, or a. mixture of the two, to produce the binding action. Usually these binders are dissolved in asolvent in order to promote penetration into the facing. After being impregnated with a suitable binder Jthe entire clutch ring or disk usually is baked to cure the binder, and if desired it may also be pressed to bring the facing down to the desired thickness. Sometimes it is necessary to sand or grind the opposite surfaces slightly for this purpose.

Clutch rings or disks in which the asbestos facing is built into the ring have been made heretofore, and their advantages are well understood byV those skilled in this art. In none of these prior constructions, however, so far as I am aware, has the facing been united to the bodyY ofthe ring or disk by manipulating a yarn so asto form stitches. rIbis method etliects'substantial economies in the manufacture of a. clutch element of'this ty ie. It is also unnecessary in making a ring according to `this process to leave the ends of the slots open, as has been necessary inthe more common, if not all, of the prior construc ions. This invention, therefore, producesa disk which, if made of the same weight of metal as prior rings, is very much stronger mechanically. In fact, the metal disk can be made of relatively thin metal and the teeth given the desired thickness by folding the metal. Such a construction is shown in Fig. 5 iii-which the disk 2 has teeth 3 of double the thickness of the body of the disk. f

lVhile I have herein shown and describeda preferred embodiment of my invention,l it will be understood that the invention may be embodied in other forms and that the process of manufacture may be varied Ain some respects without departing from the spirit or scope of the invention.

Having thus described my invention, what I desire to claim as new is:

l. A clutch element comprising a slotted metal body with vbars separating the slots of said body, and a friction facing of yarn stitched into said slots and interlocked with the bars separating said slots,theinterlocking portions of yarn in the stitches being located in said slots.

2. A clutch element of the character dcscribed comprising a metal disk having slots therein separated by bars, and a facing of asbestos yarn arranged to form'stitches interlocked with said bars, said stitches including interlocked portions of yarn located in said slots.

scribed comprising a metal disk having slots therein separated by bars, and a facing of asbestos yarn arranged to form circumferential lines of stitches lying side by side at different distances from the center of the disk, the individual stitches being interlocked with said bars, said stitches including interlocked portions of yarn located in said slots.

il. A clutch element of the character described comprising a metal disk having substantially radial slots therein separated by bars, and a facing of yarn arranged to form circumferential lines of chain stitches lying side by side, said bars extending through the loops of the stitches, and the stitches in adja- 3. A clutch element of the character (le-- cent lines being drawn toward opposite faces of the disk.

y 5. A clutch element of the character described comprising a metal disk having a toothed outer edge and radial slots separated by bars, and a facing consisting of circumferential rows of stitches of asbestos yarn interlocked with said bars, said rows lying side by side, said stitches including interlocked portions of yarn located in said slots.

6. A lclutch element of the character described colnprisin g a nietal disk having radial slots therein and provided with a substantially continuous outer riln ofinetal, anda facing of asbestos yarn arranged to form circumferential rows of stitches lying side by side' with the bars extending through theloops of individual stitches, the interlocking portions of yarn in the stitches being located `in said slots.

7. A clutch element of the character described colnprisinga metal disk having substantially radial slots therein separated by bars, and a facing of yarn comprising circuni` ferential lines of chain stitches lying side by side, the individual stitches being interlocked with said bars and each line of stitches having the same number of strands of yarn on each side of the disk. Y'

8. A clutch element comprising a niet-al disc ofsuitable form having slots therein, adjacent slots being separated by narrow bars, and a facing on said disc 'formed of circuinferential lines of stitches of asbestos yarn, lying side by side, the individual stitches be ing interlocked with said bars, said stitches including interlocked portions of yarn located in said slots.

9. A clutch element comprising a metal disc of suitable forni having slots therein, adjacent slots being separated by narrow bars, and a facing on said disc consisting of chain stitches of yarn filling said slots, said stitches being arranged in a plurality of circuinfen ential lines side by side and enclosing said bars, said stitches being drawn in adjacent lines toward opposite faces of the disc.

l0. A clutch disc comprising a nietal disk having slots therein spaced from each other by narrow bars and a facing comprising a plurality of circumferential lines of chain stitches of yarn lying side by side, said stitches forming loops in which the bars are located.

EDWIN E. VAITE. 

